A typical sport parachute system is made up of three main components: a main parachute canopy, a reserve parachute canopy and a harness/container system.
When sport jumping first started one used military surplus equipment. The main parachute was packed in the main container and attached to a harness. The main parachute was worn on the back. The reserve canopy was packed in a reserve container that was called a chest container because it was attached to the front of the harness and worn on the chest.
When parachute manufacturers started to manufacture parachute equipment specifically for sport jumpers the same configuration was used. A main parachute canopy packed in a main container was attached to a harness and worn on the back, and a reserve parachute canopy packed in a reserve container was attached to the front of the harness.
The next evolution in sport parachute equipment was to wear both the main and reserve parachute on the back. This harness/container system was called a “piggyback.” With the older system the main container, reserve container and harness were three separate components. With the piggyback system the main container, reserve container and harness is one unit.
Smokejumpers may jump as many as three fires in one day. Currently they use a chestpack reserve and a main backpack. In order to save time, the smokejumper wears his harness and reserve chestpack, while the main backpack is kept in the loft or at a sub-base. This way, different main chutes may be readily substituted so that the smokejumper is able to make another jump before his main chute is repacked from the last jump. This very valuable operational feature will be lost in the new smokejumper parachute system if the standard piggyback system is adopted since both the reserve and the main chute will be in the same unit.